Portable belt grinder and support therefor

ABSTRACT

A PORTABLE BELT GRINDER HAVING A HOUSING, A FIRST ROLLER MOUNTED WITHIN THE HOUSING, AND AN ELONGATED INTERCHANGEABLE PLATEN SUPPORTED BY THE HOUSING AND EXTENDING EXTERIORLY OF THE HOUSING LONGITUDINALLY THEREOF. A SECOND ROLLER IS MOUNTED ON THE EXTERIOR END OF THE PLATEN AND IS SPACED A DISTANCE AWAY FROM THE HOUSING GREATER THAN THE WIDTH OF THE PLATEN. AN ENDLESS BELT OF ABRASIVE MATERIAL PASSES AROUND THE FIRST AND SECOND ROLLERS AND IS SUPPORTED BY THE PLATEN ALONG AT LEAST A PART OF ITS LENGTH, WHEREBY A FIRST PORTION OF THE BELT IS ENCLOSED WITHIN THE HOUSING AND THE SECOND PORTION EXTENDS AXIALLY EXTERIORLY OF THE HOUSING A DISTANCE GREATER THAN ITS WIDTH. A SUPPORT FOR THE GRINDER IS DISCLOSED HAVING A BASE PORTION, A WORK SUPPORTING MEMBER ATTACHED TO THE BASE PORTION, THE WORK SUPPORTING MEMBER HAVING A SLOT THERETHROUGH. A BRACKET IS ATTACHED TO THE WORK SUPPORTING MEMBER AND A SUPPORT POST IS ROTATABLY ATTACHED TO THE BRACKET. AN ARM IS MOVABLY ATTACHED TO THE SUPPORT POST AT ONE END AND IS ATTACHABLE TO THE HOUSING OF THE GRINDER AT THE OTHER END, THE ARM BEING ADAPTED TO SUPPORT THE GRINDER IN A POSITION WHEREBY THE SECOND PORTION OF THE ABRASIVE BELT MAY PASS THROUGH THE SLOT IN THE WORK SUPPORTING MEMBER.

C. E. KERR PORTABLE BELT GRINDER AND SUPPORT THEREFOR Feb. 23, 1971 5 Sheets-Sheet 1 Filed Jul 17, 1968 CHARLES E. KERR INVENTOR BUC/(HORN, BLOHE, KLA/VOU/ST 8 SPAR/(MAN ATTORNEYS Feb. 23, 1971 c. E. KERR PORTABLE BELT GRINDER AND SUPPORT THEREFOR Filed July 17, 1968 3 Sneets-Sheet 2 CHARLES E. KERR INVENTOR BUG/(HORN, BLORE, KLAROU/ST a SPAR/(MAN c. E. KERR 3,56 PORTABLE BELT GRINDER AND SUPPORT THEREFOR Feb. 23; 1971 Du R M s .R t m SN Mm w N 5 Dn/ m A e H C 3 Y B L 2 w? Q QV 8 6 9 l 7 1 Y 1 nu J d e l 1 F BUG/(HORN, BLORE, KLAROU/ST 8 SPAR/(MAN ATTORNEYS United States Patent O US. Cl. 51-148 7 Claims ABSTRACT OF THE DISCLOSURE A portable belt grinder having a housing, a first roller mounted within the housing, and an elongated interchangeable platen supported by the housing and extending exteriorly of the housing longitudinally thereof. A second roller is mounted on the exterior end of the platen and is spaced a distance away from the housing greater than the width of the platen. An endless belt of abrasive material passes around the first and second rollers and is supported by the platen along at least a part of its length, whereby a first portion of the belt is enclosed within the housing and the second portion extends axially exteriorly of the housing a distance greater than its width. A support for the grinder is disclosed having a base portion, a work supporting member attached to the base portion, the work supporting member having a slot therethrough. A bracket is attached to the work supporting member and a support post is rotatably attached to the bracket. An arm is movably attached to the support post at one end and is attachable to the housing of the grinder at the other end, the arm being adapted to support the grinder in a position whereby the second portion of the abrasive belt may pass through the slot in the work supporting member.

BACKGROUND OF THE INVENTION This invention relates to grinding machines, and more particularly, to such machines comprising an endless abrasive belt.

Grinding or surfacing machines are well known and are used for a variety of purposes. Such machines, however, have not been provided heretofore with a capability of grinding, polishing or surfacing hard-to-reach parts or areas because the abrasive belts thereof have been positioned closely adjacent to the housings of the machines.

It is thus the primary object of the present invention to provide a grinding or surfacing machine having an endless abrasive belt, a portion of which extends out beyond the housing so as to be capable of grinding, polishing and surfacing hard-to-reach parts or areas, thereby to finish the same more economically, faster and smoother than can be done by hand filing or grinding.

It is a further object of the present invention to provide such a grinding machine that will be completely portable and can be moved to the individuals work area.

It is a still further object of the present invention to provide a grinding machine that will eliminate rotary tool marks that are a predominant cause of gauling and die failure.

It is a still further object of the present invention to provide a stand for the belt grinder of the present invention that will provide adjustable support for the grinder, thereby to permit its use in a variety of positions.

"ice

SUMMARY OF THE INVENTION The belt grinder of the present invention is portable and comprises a housing, a first roller mounted within the housing and an elongated interchangeable platen supported by the housing, the platen extending exteriorly of the housing longitudinally thereof. A second roller is mounted on the exterior end of the platen, the second roller being spaced from the housing a distance greater than the width of the platen.

An endless belt of abrasive material passes around the first and second rollers and is supported by the platen along at least a part of its length. Thus a first portion of the belt is enclosed within the housing and a second portion thereof extends axially exteriorly of the housing a distance greater than its width. Means for rotating the first roller to drive the belt are also provided.

Since the second portion of the abrasive belt extends axially exteriorly of the housing a distance greater than its width, being supported by the platen, the grinder of the present invention can grind, polish or surface hardto-reach parts economically and quickly and can produce a smoother finish than was possible heretofore by hand filing or grinding. The endless nature of the abrasive belt permits surfacing without producing rotary tool marks that are the predominant cause of gauling and die failure. The portable nature of the grinder makes it possible to move the machine to the work area required.

A supporting stand is also provided for the grinder of the present invention. Such a stand comprises a base portion and a work supporting member attached to the base portion. A slot is formed in the work supporting member through which the protruding portion of the abrasive belt is adapted to pass.

A bracket is attached to the Work supporting member and a support post is rotatably attached to the bracket. An arm is movably attached at one end to the support post and is attachable at the other end to the grinder housing.

The support post is rotatable in a vertical plane. When the support post is in a vertical position, either extending upwardly or downwardly, the protruding portion of the abrasive belt is adapted to pass through the slot in the work supporting member. Rotating the support post to a horizontal position places the protruding portion of the abrasive belt in a position parallel to the work supporting member.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view, with parts broken away, of the belt grinder of the present invention shown attached to a supporting stand, an alternative position of the support post thereof being shown in phantom.

FIG. 2 is a front elevational view of the apparatus shown in FIG. 1, with the support post shown in phantom lines in its horizontal position.

FIG. 3 is a sectional view taken on line 3-3 of FIG. 1.

FIG. 4 is a sectional view taken on line 4-4 of FIG. 1.

FIG. 5 is a side elevational view, with parts broken away, of the belt grinder of the present invention.

FIG. 6 is a sectional view taken on line 6 6 of FIG. 5.

FIG. 7 is a view taken on line 7-7 of FIG. 5.

FIG. 8 is a view taken on line 88 of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT The belt grinder 10 of the present invention is illustrated in FIGS. 5-8. As there shown, the grinder 10 comprises a housing 12 having a manipulating handle 14. The housing 12 preferably has one removable side plate 16 secured in position by means of hold down nuts 18 by means of which the interior of the housing may be replaced. A second handle 20 is attached to side plate 16 (see FIG. 2),

Mounted on the side of the housing 12 is a motor 22, and this motor is preferably of the electric type. Power for the motor 22 is supplied through a line 24 to a power connection and switching mechanism 26 and thence through a line 28, being controlled by an on-ofi toggle type switch 30.

The motor 22 has a shaft 32 upon which is mounted a friction drive roller 34 for driving an abrasive belt 36. The belt 36 passes around a tensioning roller 38 (to be hereinafter described in greater detail), thence over a roller 40 mounted on the housing 12 and around an elongated platen 42 mounted at the front of the housing 12 and extending exteriorly thereof.

The platen 42 is equal in width to the belt 36. It is positioned on a dowel pin 44 extending from a block 46 attached to the housing 12, being retained by cap screws 48 (see FIG. 7). The platen 42 is thus seen to be readily interchangeable, different width platens being used with different width belts.

A roller 50 is mounted on the end of a bracket 52 attached to the exterior end 53 of the platen 42 by screws 54. Set screws 56 acting on screws 54 are provided transversely to adjust the position of bracket 52 with respect to the longitudinal axis of the platen 42 and 'by this means maintain the belt 36 in true running position (see FIG. 8).

An additional support roller 58 is mounted adjacent the front of the housing 12 and close to the platen 42. The belt 36 passes between the roller 58 and the platen 42, thus to be maintained substantially in contact with the surface of the platen 42 while it is extending exteriorly of the housing 12.

The roller 50 on the end of the platen 42 is spaced away from the housing 12 a distance greater than the width of the platen, and preferably several times the width of the platen, to permit the belt to serve hard-to-reach places.

As previously mentioned, tensioning of the belt 36 is achieved by transverse pressure exerted by the roller 38. Roller 38 is mounted on the end of a bracket 60 which is attached to the housing 12 by a shoulder bolt 62 on which the bracket is adapted to pivot. As shown in FIG. 6, bolt 62 has a socket head 64 and a shoulder 66 around which is wrapped a coiled spring 68. One end 69 of the spring 68 is received in the head 64 and the other end of the spring 70 is retained against a pin 71 attached to the housing 12. The spring '68 urges the roller 38 on the end of the bracket 60 transversely against the belt 36, thereby to maintain the same under the required degree of tension. Since the top of the housing 12 is open, it is only necessary to lift roller 38 away to replace a belt.

FIGS. l-4 illustrate the stand which is particularly adapted to support the belt grinder 10 of the present invention. As shown, the stand 100 comprises a pedestal 102 supported on two casters 104 and a fixed floor-engaging post 106. A post 108 is received in a socket 110 in the pedestal 102, being retained therein by a set screw 112.

A horizontal support member 114 is mounted on top of the post 108 being retained in position by a set screw 116. Member 114 has a horizontal portion 118 to which a work supporting table 120 is attached by bolts 122. Member 114 also has an upturned vertical portion 124 which serves as a bracket to which a supporting post 126 is rotatably attached.

The table 120 has a horizontal work supporting surface having a longitudinally extending slot 127 therein. A slidable member is provided to fit in the slot 127, being adjustably retained by a hold down nut 128. Use

4 of member 125 permits an opening of any desired size to be formed in the member 120, and this opening is adapted to receive the exterior end of the belt 36 in a manner to be hereinafter described.

The support post 126 is received in a socket 130 mounted on a horizontal pivot shaft 132, one end 133 of which is threadedly received into the vertical bracket 124 of the member 114, the other end 134 being threadedly received into an actuating handle 135.

A spring loaded plunger 136 is also received in the bracket 124. The inner end 138 of the plunger 136 rides on the forward surface 140 of the socket 130 and is receivable in any one of three recesses 142a, 14217 and 1420 in the socket 130 to fix the support post 126 respectively in an upwardly extending position, a horizontally extending position, or a downwardly extending position, as desired (see FIG. 4).

FIG. 1 shows the support post 126 in its upwardly extending vertical position in solid lines. Loosening the handle from the threaded end 134 of the pivot shaft 132 and pulling the plunger 136 forwardly to release it from the lowermost recess 142a will permit the support post 126 to be rotated in the direction of the arrow 144 in FIG. 4. The inner end 138 of the plunger 136 will then ride on the surface until the plunger is received in the recess 14212 whereupon the support post 126 will be in a horizontal position (as shown in phantom lines in FIG. 2). A further rotation of the support post will lock the plunger 136 in the recess 1420, thereby to position the support post 126 in a downwardly extending position (as shown in the phantom lines in FIGS. 1 and 2).

An arm 146 terminating at one end 148 in a socket 150 is received upon the support post 126 and is movable thereon by means of a pinion 151 in the socket 150 actuated by a crank 152, which pinion rides on a rack 154 attached to the side of the support post 126. The arm 146 is locked in position with respect to the post 126 by a locking arm 156.

The forward end 158 of the arm 146 is attached to a stud 160 on the housing 12 of the belt grinder 10, being retained thereon by a nut 162. Releasing the torque on the nut 162 permits a small amount of rotation to occur between the housing 12 and the arm 146, the rotation being limited by the permissible travel of a stud 164 in an arcuate slot 166 in the housing 12 (see FIG. 5).

The arm 146 is thus seen to be vertically movable upon the support post 126 by means of the rack 154 and pinion 151. When the support post 126 is in its upwardly extending vertical position, as shown in the solid lines in FIG. 1, the exterior portion of the belt 36 on grinder 10 is seen to extend downwardly into the slot 127 in the table 120, the position of slidable member 125 being adjusted to regulate the opening to the desired size. Work to be ground can then rest on the table 120 and be worked on by the exposed portion of the belt 36.

When the support post 126 is rotated to its horizontal position as shown in phantom lines in FIG. 2, the platen 42 and the abrasive belt 36 passing therearound extend parallel to the table 120. Finally, when the supporting post 126 is rotated to its downwardly extending position, as shown in the phantom lines in FIGS. 1 and 2, the exterior portion of the belt 36 is seen to protrude upwardly through the opening 127 in the table 120, the slidable member 125 again being adjusted to regulate the size of the opening as desired.

In the foregoing description, the invention has been described witlr reference to a certain particular preferred embodiment, although it is to be understood that the specific details shown are merely illustrative and that the invention may be carried out in other ways without departing from the true spirit and scope of the following appended claims.

I claim:

1. A portable belt grinder comprising a housing;

a first roller mounted within said housing;

an elongated platen supported by said housing, said platen extending exteriorly of said housing longitudinally thereof;

a second roller mounted on the exterior end of said platen, said second roller being spaced from said housing a distance greater than the width of said platen;

an endless belt of abrasive material passing around said first and second rollers and being supported by said platen along at least a part of its length, whereby a first portion of said belt is enclosed within said housing and a second portion thereof extends axially exteriorly of said housing;

a support roller mounted within said housing adjacent the interior end of said platen, said belt passing between said support roller and said platen to main tain said belt in contact with said platen substantially throughout said second portion thereof; and

means for rotating said first roller to drive said belt.

2. The grinder of claim 1, further comprising a block attached to the interior of said housing, a pin mounted on said block, a hole in the interior end of said platen to receive said pin, and means removably to attach said interior end of said platen to said block.

3. The grinder of claim 1, further comprising a bracket mounted on said exterior end of said platen, said second roller being attached to the exterior end of said bracket, and means transversely to adjust the position of said exterior end of said bracket with respect to the longitudinal axis of said platen to maintain said belt in true running position.

4. In combination,

a portable belt grinder, and

a stand to support said grinder,

said grinder comprising a housing;

a first roller mounted within said housing;

an elongated platen supported by said housing, said platen extending exteriorly of said housing longitudinally thereof;

a second roller mounted on the exterior end of said platen, said second roller being spaced fromsaid housing a distance greater than the Width of said platen;

an endless belt of abrasive material passing around said first and second rollers and being supported by said platen along at least a part of its length, whereby a first portion of said belt is enclosed within said housing and a second portion thereof extends axially exteriorly of said housing a distance greater than its width; and means for rotating said first roller to drive said belt. said stand comprising a base portion;

a work supporting member attached to said base portion, said work supporting member having a slot therethrough;

a bracket attached to said work supporting memher;

a support post rotatably attached to said bracket;

and

an arm movably attached at one end to Said support post and attachable at the other end to said housing of said grinder, whereby said second portion of said grinder belt is adapted to pass through said slot in said work supporting member of said stand.

5. The combination of claim 4 further comprising a horizontal pivot shaft mounted on said bracket, said sup port post being rotatable in a vertical plane about said pivot shaft, and means to lock said support post in a plurality of positions in said vertical plane.

6. The combination of claim 4 further comprising a rack attached to one side of said support post, a pinion mounted on said one end of said arm, said arm being movable along said rack by said pinion and means to lock said arm in a plurality of positions along said support post.

7. The combination of claim 4 further comprising a plate slideably mounted in said slot in said work supporting member, and means releasably to fasten said plate to said member, thereby to regulate the size of the opening therein.

References Cited UNITED STATES PATENTS 1,738,873 12/1929 De Walt 51-174 1,752,133 3/1930 Wolganood 51174 1,920,364 8/1933 Degen 51--170.4

OTHELL M. SIMPSON, Primary Examiner U.S. Cl. X.R. 51170 

